Gene for biosynthesis of core structure of ophiobolin

A method for preparing an ophiobolin precursor, the method comprising:

• 1) extracting RNA from mycelia of Aspergillus sp. 094102 which has been deposited in China Center for Type Culture Collection (CCTCC) with an accession number:
• CCTCC NO. M208153;
• 2) reverse-transcribing the RNA of 1) into a cDNA;
• 3) conducting PCR amplification of the cDNA of 2) with a pair of primers to obtain a PCR product mixture;
• 4) recovering a target DNA fragment from the PCR product mixture of 3), wherein the target DNA fragment comprises the nucleic acid sequence of SEQ ID NO:
• 2 ligated to recognition sites of restriction enzymes Nde I and Hind III;
• 5) ligating the target DNA fragment into a first vector to obtain a first recombinant plasmid;
• 6) digesting the target DNA fragment from the first recombinant plasmid of 5) and inserting the target DNA fragment into a second vector to obtain a second recombinant plasmid;
• 7) transforming the second recombinant plasmid of 6) into Escherichia coli BL21 to obtain an engineered Escherichia coli strain;
• 8) cultivating the engineered Escherichia coli strain of 7) to obtain a target protein encoded by the target DNA fragment;
• 9) purifying the target protein;
• and
• 10) in vitro synthesizing an ophiobolin precursor from a first substrate and a second substrate using the target protein as a catalyst, wherein the first substrate is selected from dimethylallyl diphosphate, geranyl diphosphate, farnesyl diphosphate, and geranylgeranyl diphosphate, the second substrate is isopentenyl diphosphate, and the ophiobolin precursor has a molecular structure as follows:

A recombinant plasmid, wherein:

• the engineered plasmid is a pET28a vector comprising a target DNA sequence;
• and
• the target DNA sequence comprises the nucleic acid sequence of SEQ ID NO:
• 2.